code: def export_constant_pad_negative_axes() -> None:
      node = onnx.helper.make_node(
          "Pad",
          inputs=["x", "pads", "value", "axes"],
          outputs=["y"],
          mode="constant",
      )
      x = np.random.randn(1, 3, 4, 5).astype(np.float32)
      pads = np.array([0, 3, 0, 4]).astype(
          np.int64
      )  # pad order [x1_begin, x2_begin, ..., x1_end, x2_end, ...]
      value = np.float32(1.2)
      axes = np.array([-3, -1], dtype=np.int64)
      y = pad_impl(
          x,
          pads,
          "constant",
          1.2,
          [-3, -1],
      )
  
      expect(
          node,
          inputs=[x, pads, value, axes],
          outputs=[y],
          name="test_constant_pad_negative_axes",
      )
  
file_path: onnx/onnx/backend/test/case/node/pad.py
imports: import numpy
  import onnx
  from onnx.backend.test.case.base import Base
  from onnx.backend.test.case.node import expect
label_desc: Use image node_id 4 for calling the Pad obj's underlying member method code with example usage: obj.export_constant_pad_negative_axes() without return types